COMPARISON OF TRIBOLOGICAL BEHAVIOR OF NYLON ARAMID POLYMER COMPOSITE FABRICATED BY FUSED DEPOSITION AND INJECTION MOLDING PROCESS

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1 International Journal of Mechanical Engineering and Technology (IJMET) Volume 9, Issue 13, December 2018, pp , Article ID: IJMET_09_13_075 Available online at aeme.com/ijmet/issues.asp?jtype=ijmet&vtype= =9&IType=13 ISSN Print: and ISSN Online: IAEME Publication Scopus Indexed COMPARISON OF TRIBOLOGICAL BEHAVIOR OF NYLON ARAMID POLYMER COMPOSITE FABRICATED BY FUSED DEPOSITION MODELING AND INJECTION MOLDING PROCESS J Nagendra Senior Assistant Professor, Department of Mechanical Engineering, New Horizon College of Engineering, Bangalore, INDIA M S Ganesha Prasad Professor, Department of Mechanical Engineering, New Horizon College of Engineering, Bangalore, INDIA S Shashank, Syed Md. Ali Student, Department of Mechanical Engineering, New Horizon College of Engineering, Bangalore, INDIA ABSTRACT In the present work, the tribological properties of Nylon Aramid Polymer Composite fabricated using the fused deposition modelling (FDM) and Injection Molding process are compared. Under dry sliding conditions at room temperature, the sliding wear behaviour of FDM-built parts with two different Raster angle orientations and Injectionn Mold part were investigated and compared. The Loads of 10N, 20N and 30N were applied at a sliding velocity of 1.4 m/s for durations of 30 minutes. The results of FDM built Nylon Aramid Polymer Composite with 0 and 45 raster angle showed that the wear resistance was more by 51%. The FDM part built by 45 raster angle exhibited higher wear resistance, coefficient of friction, and friction force than that of 0 by 51%, 14% and 23% respectively. However the Injection mold part had less wear rate, similar coefficient of friction and less friction force than the FDM printed part with 45 raster angle. It was also observed that the part fill density and raster angle selection decided the part strength and better tribological properties. Keywords: Aramid Fiber, Fused Deposition Modeling, Polymer composite, Tribological properties, Pin-on-disc. IJMET/index.asp 720 editor@iaeme.com

2 J Nagendra, M S Ganesha Prasad, S Shashank and Syed Md. Ali Cite this Article: J Nagendra, M S Ganesha Prasad, S Shashank and Syed Md. Ali, Comparison of Tribological Behavior of Nylon Aramid Polymer Composite Fabricated by Fused Deposition Modeling And Injection Molding Process, International Journal of Mechanical Engineering and Technology, 9(13), 2018, pp INTRODUCTION Injection molding is a conventional manufacturing process of polymers in large scale, higher accuracy and better production rate. Injection mold process includes the extrusion unit, die pair, guiding element, and ejection system. However the process is not economically feasible for the new product development, as the dimensions of the parts are altered often until the desired design is achieved. Under these circumstances, Additive manufacturing is preferred over the conventional manufacturing process. Building the parts layer by layer from the Computer Aided Design (CAD) data file is the working principle of Additive Manufacturing [1]. The sliced section of the part is then deposited on the build plate and the new stable layer is established after its cooling [2]. The quality of parts produced by FDM process is a function of material used, part geometry, and process parameters. There are significant innovations happening from the past few years towards the process parameter optimization and the part quality enhancement. Few of the most commonly used polymer raw materials for FDM include wax, cermet, ceramics, nylon composites, glass composites, metal-polymer powders, metals, alloys, steel and polymers. Acrylonitrile-Butadiene-Styrene (ABS), casting wax, Poly carbonates and Nylon family.[3-6]. Selection of appropriate process parameters yields the product with higher strength and accuracy. Many combinations of materials are tried out to enhance the material characteristics. Nylon has distinct wear resistance characteristics due to its higher chemical bonding. The material composition of Nylon Aramid Polymer Composite (NAPC) is achieved by dry powder impregnation process [7]. In tribological aspects, there have been many studies about the investigation on the wear characteristics and frictional behavior of the Nylon based polymer composites with phenolic resin, PPS, polyimide, UHMWPE, Poly Ether Ether Ketone, epoxy, polydopamine [8-16]. In the present work, the Nylon Aramid Polymer Composite is produced by impregnation technique with variable material composition based on weight percentage (wt%). Nylon pellets and the short fibers of Aramid spool was extruded in the form of spool, and used as raw material for FDM printing [17]. The printed parts were tested for their Tribological behavior under variable loading conditions. The testing was performed as per ASTM testing standards. The optimized process parameter from Taguchi design of experiments was used to print the part at higher accuracy. However, the Injection mold part of the similar dimension was manufactured by using the same NAPC. Both the test samples weighed close to each other, as the FDM printing was done at 100% fill density. The tests were further conducted to investigate the product characteristics subjected to Tribological study. 2. MATERIALS AND METHODOLOGY MATERIAL PREPARATION Nylon-6 Pellets were utilized in the process of composite preparation. Average granule size of 4mm pellets were blended with epoxy hardened aramid short fiber with a ratio of 98:2. NAPC consists of 2 wt% of Aramid fiber reinforced with Nylon matrix. The Tribological behavior was analyzed with the combination of Aramid content varying from 0 wt%, 1 wt% and 2 wt% in the NAPC. However, increase in the Aramid content led to the clogging of the FDM IJMET/index.asp 721 editor@iaeme.com

3 Comparison of Tribological Behavior of Nylon Aramid Polymer Composite Fabricated by Fused Deposition Modeling And Injection Molding Process extruder nozzle of 0.4 mm diameter. The increase in Aramid content yielded in higher wear resistance for the composite but was not feasible enough to print the material and hence the combination was limited to 2 wt%. The blended material was extruded to a spool of 3mm standard diameter at a barrel temperature of 180 C. Figure 1(a) shows the pellets of Nylon-6 before extrusion. Aramid yarn was utilized in order to prepare the reinforcement material, the yarn was treated with epoxy resin for 2 hours and dried for 24 hours. The stiffened yarn was further chopped in to small fibers of an average length of 4 mm. The chopped fiber is shown in figure-1(b). The specified ratio of 98:2 between Nylon and Aramid fibers was done for a weight of 5 Kilograms. The material was fed into the extruder and the mandrel of 3 mm was used to extrude the spool. The extruded spool is shown in figure-1(c). The newly developed spool material was used to print the sample at the optimized process parameters of FDM. (a) (b) (c) Figure 1: (a) Nylon-6 pellets, (b) Aramid short fiber and (c) Extruded spool Cura slicing software was used by the FDM machine. The FDM printer was set at an extrusion temperature of 290 C and the bed temperature of 80 C. The sample as per the ASTM standard was modelled and printed by using Cura software. The samples were printed with two orientations, 0 parallel path and 45 cross flow path. The quality and the product strength is directly dependent on the printing parameters opted for printing. The parameters that affect the quality of the FDM part are raster angle, layer thickness, print orientation and slicing thickness. However, the parameters such as printing temperature, printing velocity, infill density, printing bed temperature, build plate adhesion and fill pattern decide the part strength. Significant importance were provided in selecting the printing parameters of FDM based on the expected desirable Tribological characteristics. The Printing parameters adopted for the work piece preparation is listed in table 1. The FDM printer was equipped with All metal filament extruder that could reach the maximum temperature of 340 C and the printing had an integrated heating plate that could reach the temperature of 100 C. Printing the work pieces on the platform having elevated temperature greater than the room temperature reduces the thermal warpage that is often observed for thicker parts. IJMET/index.asp 722 editor@iaeme.com

4 J Nagendra, M S Ganesha Prasad, S Shashank and Syed Md. Ali (a) (b) Figure 2. (a) FDM printer with thermal platform and (b) FDM printed NAPC model The work piece was printed with the following printing parameters and three replications were considered for testing to avoid the ambiguity in the results. The value of the printed parameter for the work piece with 0 orientation is listed as A and the values for the work piece with 45 orientation as B in the table 1 respectively. The corresponding orientations are shown in figure 3. Figure 3. FDM print orientation at 0 and 45 orientation Table 1. Printing parameter of CURA Parameters A B Layer thickness 0.4 mm 0.4 mm Brim Line width 0.4 mm 0.4 mm Side wall thickness 0.8 mm 0.8 mm Top layer and bottom layer thickness 0.8 mm 0.8 mm Infill Density 90% 90% Infill pattern Lines Zig-Zag Printing temperature 280 C 280 C Build plate temperature 80 C 80 C Filament diameter 3 mm 3 mm Deposition speed 60 mm/sec 60 mm/sec Build plate adhesion type Brim Brim IJMET/index.asp 723 editor@iaeme.com

5 Comparison of Tribological Behavior of Nylon Aramid Polymer Composite Fabricated by Fused Deposition Modeling And Injection Molding Process However, the Injection Molded work piece with the NAPC was also prepared according to the ASTM D99 Standard. The weight of the Injection mold part with respect to the FDM printed part was almost equal to each other. The Injection molded part weighed about 310 mg and the FDM printed models weighed about 305 mg. The Injection Mold machine was operated using the setting mentioned in the table 2. Table 2. Injection Mold parameters Parameters A Cylinder temperature 260 C Primary pressure 50 to 70 N/mm 2 Secondary pressure 40 to 60 N/mm 2 Back pressure 3 to 5 N/mm 2 Mold temperature 80 C to 100 C 3. EXPERIMENTATION The prepared NAPC work pieces were subjected to the Pin-on-disc wear resistance test as per ASTM D99. The testing were done to evaluate the wear and friction monitoring. The work pieces were tested for its Tribological properties by Ducom wear and friction monitor TR- 20LE-PHM-CHM-400 instrument which had a rotary drive to control the disc rotation. The cylindrical work-piece was loaded accordingly to attain the desirable stresses within the material for appropriate validation. The experimentation work flow is mentioned in the figure 4. The work-pieces were rigidly held against a rotary disc under viable steady load. FDM work-pieces with 0 and 45 orientation were held against the rotary disc. The loads were varied from 10 kn, 20 kn and 30 kn accordingly. WINDUCOM 2010 measured the Tribological properties of the work-pieces. This test enabled in understanding the behaviour of the work-pieces under different loading conditions. The experimental results also revealed the friction force and coefficient of friction along with the wear rate. 4. RESULTS AND DISCUSSION RESULT Figure 5, (a-i) determines the test results plotted by the WINDUCOM 2010 for the respective work-pieces. (a) (b) IJMET/index.asp 724 editor@iaeme.com

6 J Nagendra, M S Ganesha Prasad, S Shashank and Syed Md. Ali (c) (d) (e) (f) (g) (h) IJMET/index.asp 725 editor@iaeme.com

7 Comparison of Tribological Behavior of Nylon Aramid Polymer Composite Fabricated by Fused Deposition Modeling And Injection Molding Process (i) Figure 5. Tribological Results from WINDUCOM 2010 The extreme left of the individual table represents the wear rate, right top left window determines the coefficient of friction and the lower right window determines the friction force in Newton for the respective tests. Three work-pieces under three loading conditions were performed and the figure 4 exhibits the test results. The plotted values of the respective workpieces against the testing conditions are represented in the Table 3 for a steady load on 10kN. Table 3. Test result under 10 kn load Parameters 0 45 IM wear (µm) Coefficient of friction (µ) Friction force (N) Table 4. Test result under 20 kn load Parameters 0 45 IM wear (µm) Coefficient of friction (µ) Friction force (N) Table 4 and 5 determines the value of the wear, coefficient of friction and friction force for a load of 20 KN and 30 kn for the FDM printed work-pieces with 0, 45 orientation and Injection Mold work-piece. Table 5. Test result under 30 kn load Parameters 0 45 IM wear (µm) Coefficient of friction (µ) Friction force (N) The consolidated average readings for the load of 10kN, 20kN and 3kN are listed in the Table 6. IJMET/index.asp 726 editor@iaeme.com

8 J Nagendra, M S Ganesha Prasad, S Shashank and Syed Md. Ali Table 6. Consolidated average values Parameters 0 45 IM wear (µm) Coefficient of friction (µ) Friction force (N) DISCUSSION The three test samples of 0, 45 orientation and IM sample, under the load of 10 kn exhibited a wear of 67µm, 25µm and 8.5µm respectively. For a load of 20 kn, the wear were 28µm, 26µm, 16µm and for 30 kn load the wear of 31µm, 11µm and 7µm were observed. The measured coefficient of friction for the load of 10 kn were 0.29, 0.33, 0.31, for the load of 20 kn were 0.43, 0.36, 0.24 and for the load of 30 kn were 0.425, 0.3 and The friction force of 3.25N, 3N and 2.8N were observed for 10kN of load, 8.5N, 7N, 4.5N for 20 kn and 13N, 9N and 8.5N for the load of 30 kn were noticed. The wear resistance was offered more by the FDM printed sample with 45 orientation under all the three loading conditions as compared to the sample with 0 orientation. The work-piece with 45 orientation revealed the importance of the raster angle and that had a significant resistance in wear and reduction in friction force and coefficient of friction. The work-piece of 45 orientation offered the wear resistance by 51% higher than the 0 orientation, 14% low coefficient of friction, 23% lesser friction force respectively. Figure 6. Surface plot 6. CONCLUSION Figure 6 shows the surface plot of the test results. From the investigation it was possible to conclude that the process parameters of Fused Deposition Modelling out of which the raster angle decided the Tribological characteristics of the FDM samples. However, other printing parameters also have vital contribution in achieving the desirable characteristics. The part printed from the optimized printing parameter yielded the part with 51 % higher wear resistance, and 23% reduction in friction force. It was also possible to conclude that the increase in the raster angle resulted in the part with better Tribological properties. It would strongly be recommended to print the FDM samples with 45 orientation for enhanced Tribological characteristics. However, it was not still possible to meet the Tribological properties of the Injection Molded part. The FDM sample with 45 raster angle was inferior by 49% in wear resistance, 15% in coefficient of friction and 17% in friction force. The properties of the FDM parts can still be enhanced by reducing IJMET/index.asp 727 editor@iaeme.com

9 Comparison of Tribological Behavior of Nylon Aramid Polymer Composite Fabricated by Fused Deposition Modeling And Injection Molding Process the fill density and reinforcing the cavities with thermoplastic resins that will offer higher chemical bonding resulting in lower frictional losses and enhanced tribological characteristics. REFERENCES [1] Mohamed, O.A.; Masood, S.H.; Bhowmik, J.L. Optimization of fused deposition modeling process parameters: a review of current research and future prospects. Advances in Manufacturing 2015, 3, [2] D Akinci, A., Sen, S., and Sen, U., Friction and wear behavior of zirconiumoxide reinforced PMMA composites. Composites: Part B, 56, [3] Prashanth K Jain et. al. Advances in materials for powder based rapid prototyping, International Conference on recent advances in materials and processing, Dec 15 (2006). [4] R D Goodridge et. al. Laser sintering of polyamides and other polymers, progress in material science, Vol 57, p (2012). [5] C Ramesh et. al. High temperature X-ray Defraction studies on the crystalline transition in the α and γ form of nylon, Macromolecules Vol 34, Issue 10, P (2001). [6] Siddhart Ram Athreya et. al. Processing and characterization of a carbon black filled electrically conductive Nylon-12 nanocomposite produced by SLS, Material Science and Engineering, Vol A 527, P (2010). [7] M. Rath, S. Kreuzberger and G Hinirichsen. Manufacturing of aramid fiber reinforced nyon-12 by dry powder impregnation process, Composite part A 1998, [8] Mohan N, Natarajan S. Sliding wear behaviour of graphite filled glass-epoxy composites at elevated temperatures. Poly. Plast. Technol. Eng [9] Basavarajappa, S.; Yadav, S.M.; Kumar, S.; Arun, K.V.; Narendranath, N. Abrasive wear behavior of granite-filled glassepoxy composites by SiC particles using statistical analysis. Polym. Plast. Technol. Eng. 2011, 50, [10] Srivastava, S.; Tiwari, R.K. Synthesis of Epoxy-TiO2 Nanocomposites: A study on sliding wear behavior, thermal and mechanical properties. Int. J. Polym. Mater. 2012, 61, [11] Bonaccorso, F.; Lombardo, A.; Hasan, T.; Sun, Z.; Colombo, L.; Ferrari, A.C. Production and processing of graphene and 2d crystals. Mater. Today 2012, 15, [12] Ren, G.; Zhang, Z.; Zhu, X.; Ge, B.; Guo, F.; Men, X.; Liu, W. Influence of functional graphene as filler on the tribological behaviors of Nomex fabric=phenolic composite. Compos. Pt. A 2013, 49, [13] Pan, B. Zhao, J. Zhang, Y. Zhang, Y. Wear Performance and mechanisms of polyphenylene sulfide=polytetrafluoroethylene wax composite coatings reinforced by graphene. J. Macromol. Sci., Phys. 2012, 51, [14] Pan, B.-L. Xing, Y.-L. Liu, J.-C. Liu, J.-L Zhao, J.; Zhang, Y.-Q.; Zhang, Y.-Z. Tribological behavior of PPS coating modified by graphene. Mocaxue Xuebao=Tribology 2011, 31, [15] Zhang, L.-B. Wang, J.-Q.;Wang, H.-G.; Xu, Y.; Wang, Z.-F.; Li, Z.-P.; Mi, Y.-J.; Yang, S.-R. Preparation, mechanical and thermal properties of functionalized grapheme polyimide nanocomposites. Compos. Pt. A 2012, 43, [16] Liu, H.; Li, Y.; Wang, T.; Wang, Q. In situ synthesis and thermal, tribological properties of thermosetting polyimide graphene oxide nano composites. J. Mater. Sci. 2012, 47, [17] Nagendra J, Dr. M S Ganesha Prasad, Tribological characterization of FDM component using aramid fiber reinforced with nylon, International Journal of Research in Aeronautical and Mechanical Engineering, 2016, Vol 4 issue 1, IJMET/index.asp 728 editor@iaeme.com